[oftenwrong]

I also do not use an alarm if I can avoid it. I have not used one regularly in over 15 years. Regrettably, my partner uses an alarm, so I am sometimes unable to avoid being woken by an alarm. Some thoughts on this:

1. Being awoken by an alarm is stressful. Waking up naturally, when my body is ready to wake up, feels great, and is easy. I have no trouble energetically hopping out of bed when I awake naturally. When I awake to an alarm, it is a struggle to get out of bed.

2. If I am awoken by an alarm during deep sleep, I consider that a waste of restful sleep potential. Returning to sleep for a brief period ("snoozing") does not make one less tired in any significant way. Deep sleep is what really matters, so it should not be wasted.

3. Like you said, the easy way to wake up on time without an alarm is to go to bed early. I allocate more hours for sleep than actually needed. If I wake up earlier than needed, that is no problem. If I have trouble falling asleep, or have poor sleep quality for any reason, the extra time can smooth out the impact. Having a time buffer prevents oversleeping.

4. I use an eye mask or blackout curtains to keep light from windows or electronic devices from disturbing my sleep. Most people think that small amounts of light do not bother them. I used to think the same, but I have come to believe it makes a significant difference. Complete darkness makes for high quality sleep. Light can disturb sleep just as much as noise. If you live in a fairly populated area, like I do, the sky is quite lit up at night. Like many people, I avoid screens and light in general close to my bed time.

[nradov]

Why is being awoken by an alarm stressful? It never bothered me. In fact I find it more stressful to not have an alarm set due to the fear of being late for work or an appointment. If I wake up before the alarm it's easy to turn off.

[alleyshack]

Not OP, but for me, it's the jarring-ness of the alarm. A year or so ago, I noticed it's easier to wake up at 6:30am during the summer, when the sun rises and I'm waking up to sunlight. During the summer, I'd usually wake up on my own anywhere from 5-20 minutes before my alarm went off, and it was a comfortable waking up. However, in the winter, I'd be jarred awake by an alarm to a pitch-black room, often smack in the middle of a sleep cycle, leaving me groggy and sluggish.

Once I realized that, I bought a $30 light alarm. It starts to glow softly about half an hour before my desired wake-up time, and except for once or twice when I was too buried under the covers to see the light, it consistently wakes me much more smoothly and pleasantly than getting jarred awake by a jangling alarm. (It has a back-up audio alarm that plays at your normal wake-up time, which shuts off when you turn off the light part.)

[wpietri]

Yes, exactly. A jarring alarm will wake me up wherever I am in my sleep cycle, and I get the same grogginess. A light alarm gets me to wake up when my body is ready to wake.

I found off-the-shelf light alarms not bright enough, so I used a bunch of Hue lights to get it brighter:

https://github.com/wpietri/sunrise

I was surprised to discover that the more valuable part was auto-dimming the lights in the evening. I'm much more likely to go to bed on time if there's been a virtual sunset over an extended period. I miss it when I travel.

[nradov]

I'm not sure what the sleep cycle has to do with it. I feel the same way regardless of when the alarm wakes me up.

[oftenwrong]

Like the other user said, it is jarring. Observe a person in deep sleep waking up to an alarm. They will have a brief moment of panic as they are abruptly jolted out of sleep. An alarm that gradually increases in volume is better, but still aggravating. A light-based alarm is significantly better. The best, by far, is allowing oneself the time to wake up naturally, when the body is ready, with no artificial sleep interruption.

[nradov]

I guess it varies by person. I don't find alarms jarring or panic inducing.